How controlled demolition is done

All demolition works undertaken by a qualified and experienced demolition contractor are completed in a controlled environment. This ensures the safety of the demolition team, other contractors and stakeholders, and the surrounding general public.


Generally speaking, the term ‘controlled demolition’ refers to the demolition of a building or structure by means of explosives. Demolition using explosives, sometimes called implosion, ensures the strategic collapse of a building or structure by placing explosive materials in a predetermined, detailed sequence and detonating them at a pre-arranged time.


Site preparation for demolition is detailed and thorough, regardless of the method of demolition. When preparing a site for demolition by explosive means it all depends on the structure. A simple structure like a chimney can be prepared for a controlled demolition in less than a week but larger, more complex or multiple structures can take up to six months of preparation to remove internal walls, drilling holes for placing of explosives, wrapping columns with fabric and fencing before firing the explosives.


Although using explosives as a method to demolish indicates that the building or structure will be blown up, this is not actually the case. Controlled demolition employs a series of small explosions, strategically placed within a structure, progressively detonated encouraging a collapse by weakening or removing critical supports. Explosives on the lower floors then initiate a controlled collapse and the building fails under its own weight, succumbing to gravity.


Controlled demolition can be used on virtually any type of structure but is commonly utilized on buildings of significant height, bridges, chimney stacks and cooling towers. Tall buildings, such as tower blocks, are typically seen as the main structures demolished by controlled demolition. It is essentially more cost and time efficient in bringing down a building of significant size and height to use explosives. Use of this method all depends on the surrounding area and whether there are other buildings in close proximity, and tenants and /or residents occupying those buildings. The local environment and wildlife are also taken into consideration.

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